title: A comparison of pediatric, adolescent, and adult testicular germ cell malignancy.
abstract: BACKGROUND
  Testicular germ cell tumors (T-GCTs) occur from infancy to adulthood, and are the most common solid tumor in adolescent and young adult males. Traditionally, pediatric T-GCTs were perceived as more indolent than adult T-GCTs. However, there are few studies comparing these groups and none that specifically evaluate adolescents.
  
  
  METHODS
  An institutional database of T-GCT patients was reviewed and patients were categorized into Pediatric, aged 0-12 years, Adolescent, aged 13-19 years, and Adult, older than 20 years, cohorts. Demographics, tumor characteristics, disease stage, treatment, event-free survival (EFS), and overall survival (OS) were compared between groups.
  
  
  RESULTS
  Overall, 413 patients (20 pediatric, 39 adolescent, 354 adult) met study criteria and were followed for a median of 2.0 years (0.1-23.6). Adolescents presented with more advanced stage than children (P = 0.018) or adults (P = 0.008). There was a higher rate of events in Adolescents (13, 33.3%) than in Adults (61, 17.2%) or Children (2, 10.0%). Three-year EFS was 87.2% in the Pediatric group, 59.9% in Adolescents and 80.0% in Adults (P = 0.011). In a multivariate analysis, controlling for stage, IGCCCG risk, and histology, the hazard ratio (HR) for an event was: 1 (Reference) for Adults, HR = 0.82 (95% CI 0.19-3.46; P = 0.33) for the Pediatric group, and HR = 2.22 (95% CI 1.21-4.07; P = 0.01) for Adolescents. Five-year OS was 100% in the Pediatric group, 84.8% in Adolescents, and 92.8% in Adults (P = 0.388).
  
  
  CONCLUSIONS
  Lower EFS in adolescent T-GCT patients was observed than in either children or adults. Elucidating factors associated with inferior outcomes in adolescents is an important focus of future research.
authors.affiliation: Division of Urologic Oncology, University of Texas Southwestern Medical Center, Dallas, Texas; Division of Urology, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Cost
authors.forename: Jessica D
authors.initials: JD
authors.lastname: Lubahn
authors.forename: Mehrad
authors.initials: M
authors.lastname: Adibi
authors.forename: Adam
authors.initials: A
authors.lastname: Romman
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Wickiser
authors.forename: Ganesh V
authors.initials: GV
authors.lastname: Raj
authors.forename: Arthur I
authors.initials: AI
authors.lastname: Sagalowsky
authors.forename: Vitaly
authors.initials: V
authors.lastname: Margulis
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D008297:Male; D009367:Neoplasm Staging; D009373:Neoplasms, Germ Cell and Embryonal / Q000401:mortality* / Q000473:pathology; D013736:Testicular Neoplasms / Q000401:mortality* / Q000473:pathology; D055815:Young Adult
keywords: adolescent oncology; germ cell malignancy; pediatric oncology; testicular cancer